Vintage Women's HEIRESS Robe Belted‎ Light Blue

Vintage Women's HEIRESS Robe Belted Light Blue.  I do not know the size, wear it was made or what kind of material it is due to the tag no longer having any print.  Laid flat measures 22" armpit to armpit and 23" at the belt and 56.5" long from the top of the shoulder to the bottom hem.  There is one pocket on the right side.  The belt loops are intact and there aren't any holes or stains.